This invention relates to locking ring metals for use in loose leaf ring binders; and, more particularly, to an improved locking ring metal.
As is well-known in the art, the purpose of a binder ring metal used to hold material, typically hole-punched sheets of paper or the like, so the material is readily available to a user and easily transported from one place to another. For this purpose, a ring metal has one or more binder rings with each ring comprising a pair of complementary shaped ring halves the outer ends of which are movable out of and into contact with each other. The holes in the paper or other material are inserted onto one of the ring halves when the binder is open, held in place when the binder is closed, and removed when the binder is again opened.
A problem with conventional ring binders is that if they are dropped or otherwise mishandled, the rings of the metal can inadvertently open allowing the contents of the binder to spill out. One approach to preventing this from happening has been to somehow lock the rings in their closed position so even if the binder is jarred, the rings remain closed and the contents secure. Various metal constructions have been developed to achieve locking of the binder rings.
One approach to solving the problem is described in U.S. Pat. Nos. 6,840,695 and 7,674,062, both to Horn, and the Horn published U.S. patent application 2006/0056906. Other recently issued patents which attempt to address the problem include U.S. Pat. No. 7,530,755 which is assigned to the same assignee as the present application, and U.S. Pat. No. 8,186,899 and published U.S. patent application 2012/0230755 both of which are assigned to World Wide Stationery Mfg. Co. Ltd.
In U.S. provisional patent application 61/727,944, filed Nov. 19, 2012 in the name of the same inventor as the current application, there is described an improvement to current locking ring metal designs. The present invention provides another improvement to these designs.